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Sürdürülebilir Kalkınma Amaçları

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• MakaleAçık Erişim2025Scopus SJRQ1/r/bayburt/12638
  Joule heating of carbon fiber in hybrid composites with glass fibers: Investigation of electro-thermal and vibration characteristics

  Uslu, Emin; Yilmaz, Galip; Uyar, Mehmet

  This study explores the innovative dual-purpose use of carbon fiber, functioning both as a structural and a heating element, expanding its potential in hybrid composites. A prototype composite was fabricated using the vacuum infusion process, featuring a single carbon fiber layer at the core for dual-purpose and two outer layers of glass fiber. Electrical heating tests revealed a stable relationship between voltage, resistance, power, and temperature, demonstrating efficient heat generation as the voltage increased. Thermal imaging confirmed uniform heat distribution with minor variations. Free vibration tests evaluated the composite's dynamic behavior under various electro-thermal conditions. Results showed that increasing temperature reduced the natural frequencies, particularly in the second vibration mode. Changes in Rayleigh damping coefficients at higher temperatures highlighted the composite's sensitivity to thermal inputs. These findings underline the potential of hybrid composites for advanced applications like turbine blades and aerospace components, where multifunctionality, self-heating, and vibration control are critical.

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• MakaleAçık Erişim2025Scopus SJRQ2/r/bayburt/11572
  Performance analysis of piezoelectric-based energy harvesting in reinforced concrete buildings under seismic and live loads

  Ergün, Mustafa; Uyar, Mehmet; Malgaca, Levent

  The demand for autonomous energy solutions in seismic regions is increasing for the uninterrupted operation of structural health monitoring systems. In this context, energy harvesting systems offer a solution for low-power devices, especially in earthquake zones where external energy sources may be interrupted. This study evaluates the energy harvesting capacity of a piezoelectric energy harvesting mechanism placed at specific locations in the columns of a reinforced concrete structure, considering both earthquake and live load conditions. A smart building model is developed by placing sensor modules with piezoelectric material on the columns of a three-story reinforced concrete building. The finite element model of the smart building, which is formed by integrating various technologies and sensors, is created in ANSYS, and specific locations on the columns are selected as sensor points. Dynamic analyses are performed under earthquake conditions by considering seismic records from the Imperial Valley, Erzincan, and Darfield earthquakes. Experimental results of a smart structure with patched piezoelectric material are used to verify the simulation results. The voltage, current, and power responses obtained from the sensor points are examined with the payload effect placed at the end point of the sensor module. When the power values collected from the sensor points are compared, it can be said that the maximum power obtained from the smart building under both earthquake and live load is 0.355 W, while the minimum power value reaches 0.168 W. The results show that the energy harvesting mechanism can provide external power to support electronic devices in regions where earthquake effects are frequent and high. Thus, this study presents an innovative contribution to smart building systems by investigating the energy harvesting potential under earthquake and live loads in a reinforced concrete structure equipped with piezoelectric sensors. The model, validated with numerical and experimental analyses, proposes a sustainable energy source for structural health monitoring systems in seismic regions.

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  AtıfScopus1·WoS1·OpenAlex3

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• MakaleYalnız künye2025Scopus SJRQ2/r/bayburt/11022
  Theoretical and experimental studies on a novel potential barrier control for a vehicle model and piezoelectric smart structure

  Uyar, M.

  A novel control methodology, inspired by the quantum mechanical phenomenon of particle-wave duality, wherein particles and waves utilize their energy to traverse potential barriers, has been proposed. This control strategy is investigated both numerically and experimentally to mitigate undesirable vibrations in a three-degree-of-freedom vehicle system and a smart beam structure. The mathematical framework for the vehicle system is derived using Lagrange’s equations, while the experimental setup is designed for the smart beam. Disturbance inputs in the form of step and sinusoidal road profiles are introduced into the vehicle model to simulate real-world conditions. For the smart beam, endpoint vibrations are induced as an initial value problem by releasing the beam’s endpoint from a predefined initial displacement. In order to achieve vibration suppression, control signals, parameterized based on system-specific frequency and period characteristics, are applied to both systems. The optimal control parameters are determined by evaluating the vibration damping performance. The findings of this study demonstrate that the proposed control strategy is not only effectively applicable to the experimental validation of the piezoelectric smart structure but also holds significant potential for numerical integration into mechanical systems, such as vehicle dynamics models.

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  AtıfScopus1·WoS1·OpenAlex1

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• MakaleAçık Erişim2024/r/bayburt/16475
  Seismic behavior assessment of RC buildings controlled by passive and active techniques

  Uyar, Mehmet; Ergün, Mustafa

  In this paper, a numerical study was carried out on the effectiveness of the active earthquake control method in improving the earthquake response of RC buildings. High damping rubber bearing design was made according to the criteria of the Uniform Building Code. Three different types of isolators were obtained geometrically. Passive earthquake control of the building was provided by placing these isolators under the columns. For active earthquake control of the building, controller design was realized by integrating it into the FE transient analysis in ANSYS. The active earthquake control design was studied using a force-based and displacement-based controller with acceleration and displacement feedback. The linear dynamic earthquake analysis in the time history of all three states of the building (un-controlled, passive, and active-controlled) was made using the acceleration record of the Seferihisar (İzmir) earthquake. When the results are examined, it is seen that the active earthquake control method provides almost all of the positive behavior expected from the passive earthquake control method. In addition, it eliminates some of the disadvantages of the passive earthquake control method.

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  AtıfOpenAlex1

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• MakaleYalnız künye2024Scopus SJRQ1/r/bayburt/13126
  Dynamic Angular Velocity Load-Based Energy Harvesting Analysis for Different Blade Angles and Polarization Directions of Smart Blades

  Uyar, M.

  Energy consumption and control of electrical devices in flying electric vehicles with propellers such as drones are important for the continuity of the movement process. With this motivation, the piezoelectric energy harvesting performances of the smart drone propeller and smart wind blades are evaluated in order to obtain electrical energy from lead zirconate titanate (PZT) material placed on the propellers. Initially, the effect of smart wind blades with different blade angles on energy harvesting analysis is examined. The energy harvesting performances of the converse (z polarization) and shearing movements (y polarization) of the PZT material placed on the wind blades are compared under different angular rotational velocities. Then, the power outputs obtained depending on the sensor responses of the smart drone propeller with different resistance gains are evaluated according to the polarization directions. The maximum and minimum power output values obtained from the smart drone propeller at 12,000 rpm rotation velocity are measured as about 0.086 and 0.008 W, respectively. The results show that the energy harvesting performance of the z-polarized smart propeller is more effective than the y polarization, and the amount of energy obtained with the increase in the endpoint vibration amplitudes increases as the rotation speed increases.

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  AtıfScopus1·WoS1·OpenAlex1

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• MakaleYayıncıda açık erişim2024Scopus SJRQ1/r/bayburt/13105
  Enhanced thermal and angular velocity-induced hybrid piezoelectric energy harvesting of smart turbine blades

  Uyar, Mehmet

  In this study, an approach is proposed to examine hybrid piezoelectric energy harvesting performances from vibrations induced by thermal and angular velocity loads in order to generate energy from the smart turbine blade. In the proposed method, a smart turbine blade is formed by patching the piezoelectric material to the root surface of the turbine blade. A finite element (FE) model of the smart turbine blade is established and then it is validated with a smart blade model in a reference study to test the reliability and accuracy of the FE method. The defined loads are applied to the smart blade to obtain energy from mechanical vibrations induced by thermal and angular velocity loads. Temperature distribution, voltage, and vibration results obtained from energy harvesting analysis under different thermal and angular velocity loads are presented. In order to investigate the energy conversion efficiency of the energy obtained from the system, the energy harvesting circuit is tested in terms of battery discharge times and power output values. The results show that while the maximum energy conversion in the thermally induced smart turbine blade is 11.9 W, a power output of 12.3 W is obtained from the hybrid energy harvesting mechanism under angular velocity and heat flux loads.

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  AtıfScopus5·WoS5·OpenAlex3

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• MakaleYalnız künye2024Scopus SJRQ2/r/bayburt/12987
  Investigation of Vibration Control Performance with Modified Motion Planning Based on Basic Functions for Composite Robot Manipulators

  Uyar, M.

  When flexible manipulators complete their movements to the desired position, vibrations occur at the endpoint. Reducing vibrations is an important advantage for eliminating positioning errors and monitoring position accuracy. However, the increase in vibration amplitudes leads to the inability to complete the planned tasks in the applications and results in loss of productivity. Therefore, the reduction of end-effector vibrations is an important research area. In this study, a motion-based control (MBC) method with designed motion profiles is introduced to reduce the endpoint vibrations of epoxy–glass-reinforced composite manipulators. Three different motion profiles, namely Modification-1, Modification-2, and Modification-3, are designed according to time and maximum velocity values depending on the system's frequencies. For the design of Modification-1, variable deceleration and acceleration times are considered, while for Modification-2 and Modification-3, both the maximum angular velocity and the deceleration and acceleration times are utilized. For two different angular positions and motion times, all motion profiles are applied to two composite manipulators with different frequencies, and the results are experimentally and numerically obtained to examine the vibration performance of MBC. Simulation results confirmed with experiments are achieved using mathematical models in ANSYS. To evaluate the effectiveness of MBC, the change in RMS values of endpoint vibration responses and the reduction rates are presented comparatively for all motion profiles. The results show significant advantages for the MBC method, reducing vibrations by approximately 99%, and eliminating positioning errors caused by vibrations.

  AtıfScopus3·WoS4·OpenAlex4

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• MakaleAçık Erişim2024Scopus SJRQ2/r/bayburt/12831
  Analysis of an actively controlled composite box manipulator without external actuator

  Lök, Şefika İ; Malgaca, Levent; Uyar, Mehmet

  This study focuses on active vibration control for a single-link composite box manipulator by using a single actuator for driving and control actions. Model extraction and system identification techniques are studied to obtain mathematical models of the manipulator. The state space model is extracted from the finite element model using modal analysis conducted in ANSYS, while the system identification approach is an experimental modeling method using the input and output signals of the system. The input signals are defined as triangular and trapezoidal motion profiles, while the output signals are the acceleration signals of the manipulator. Proportional derivative and positive position feedback controllers are implemented on the obtained mathematical models to reduce residual vibrations. The simulation results are successfully verified by experiments, and uncontrolled/controlled results are evaluated with reduction rates.

  AtıfScopus3·WoS3·OpenAlex2

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• MakaleAçık Erişim2023/r/bayburt/16574
  Study on dynamic modelling and vibration analysis of single-link flexible manipulator

  Uyar, Mehmet

  In this study, SimMechanics-based dynamic modeling and vibration analysis of a single-link flexible manipulator are studied. A flexible beam model is set up for modeling the manipulator. Transient analysis is performed to obtain the endpoint acceleration vibration responses of the manipulator moved with different motion profiles. Both the experimental and simulation acceleration results are presented for different cases. The root means square (RMS) values of the acceleration responses are calculated to evaluate the compatibility performance in verifying the simulation results with the experimental results. It has been observed that the results match each other successfully for different cases. The reliability of the SimMechanics-based dynamic modeling method of manipulators is discussed with the experimental results.

  AtıfOpenAlex3

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• MakaleYalnız künye2023Scopus SJRQ1/r/bayburt/11903
  Investigation of vibration performance of pure active single and multi-feedback controls for a tall RC building

  Uyar, Mehmet; Ergün, Mustafa

  Structural control methods are applied to eliminate the structural damages caused by the vibrations in the buildings and to improve their dynamic behavior of them under dynamic lateral loads. In this paper, the pure active control performance of a tall building under the influence of earthquake records, in which the effective time duration is determined by considering the ARIAS energy distribution, is presented. The building's pure active control performance in the period when the earthquake records have the maximum effect on the structure is examined. Eleven earthquake records are selected to better evaluate the effect of vibration control performance. A genetic algorithm is used to determine the parameters of single and multi-feedback controllers, and its effect on the vibration eliminations at the top and all floors is studied. Also, the effect of displacement and velocity feedback on seismic vibration control is evaluated. To carry out the vibration control studies of the building, the mathematical model is extracted from the finite element model created in ANSYS and verified with finite element analysis. It is observed that the displacement value at a reference location on the building is reduced from 0.735 m to 0.019 m, 0.004 m, and 0.002 m, respectively, by the Proportional-Integral-Derivative, Direct Velocity Feedback, and Optimal controllers. The results show that the multi-feedback control is more effective than the single-feedback control application in reducing the vibration amplitudes at all floors in the pure active control system.

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